Derson



(No Model.)

L. SAUNDERSON. ELECTRODE FOR ARC LAMPS.

Patented July 29, 1890.

773% ose/fed F/b/ous Plug.

UNITED STATES PATENT OFFICE.

LLEVELLYN SAUNDERSON, OF KINGSTOW'N, COUNTY OF DUBLIN, IRELAND.

ELECTRODE FOR ARC LAMPS.

SPECIFICATION forming part of Letters Patent No. 433,041, dated July 29, 1890.

Application filed May 14, 1890. Serial No. 351,798. (No model.) Patented in Belgium February 20, 1890, No. 89,570, and in Italy March 31, 1890, No, 26,956.

To all whom it may concern:

Be it known that I, LLEWELLYN SAUN- DERSON, gentleman, a subject of the Queen of Great Britain, residing at 10 De Vesci Terrace, Kingstown, in the county of Dublin, Ireland, have invented an Improvement in Electric-Arc Lighting, (for which I have re ceived Letters Patent in Belgium, No. 89,570, dated February 20, 1890, and in Italy, No.

26,956, dated March 31,1890) of which the following is a specification.

In the specification of a patent granted to me, No. 418,474, dated December 31, 1889, I have described an improvement in electricare lighting which may be shortly described as consisting in supplying hydrocarbon vapor to the are through a hollow electrode and from a tightly-fitting fibrous plug at the cool end of this electrode. The plug is allowed to absorb hydrocarbon liquid. A minute quantity of vapor finds its way into the vacant space in the electrode beyond the plug. It here becomes highly heated and in this state enters the are. By these means the light is much improved. A difficulty has, however,been experienced and inconvenience has resulted therefrom. It is that carbon is sometimes deposited at the point of the electrode where the arc is exhibited, and the paso sage of vapor is thereby impeded. The object of my present invention is to remove this defect, and thisI do by inserting a thread of asbestos or like mineral fiber or material into the void space in the electrode beyond 3 5 the tightlyfitting plug, but so, nevertheless, as to leave the space freely open. This thread does not act as a wick. In fact the fibrous plug prevents any liquid passing to it, and the thread need not be in contact with the plug. The thread, indeed, is entirely inoperative except at the point of the electrode where the are is displayed, and here it operates to prevent the growth or mushrooming of the carbon. The invention is appli- 5 cable also when coal-gas is supplied through the hollow electrode.

The drawing annexed shows the same arrangement as is shown and described in my formerspecification,with the addition to which reference has been made.

a is a vessel containing hydrocarbon oil, or it may be a hydrocarbon such as Vaseline, which when cold is solid.

Z) is the hollow carbon electrode, and c is the tightly-packed fibrous plug, which allows only a small quantity of hydrocarbon to be vaporized within the electrode. This electrode is used in conjunction with a second electrode of carbon, which may be either hollow or solid, and there are usual devices Go for the production of the electric are between the electrodes.

(Z is the asbestus thread, which I now provide within the electrode for the purpose already stated. It does not fill the passage in the electrode, and offers no appreciable obstruction to the flow of the hydrocarbon vapor.

Illuminatinggas maybe supplied to the hollow electrode in place of hydrocarbon liquid. Gas has the same tendency as hydrocarbon vapor to cause deposition of carbon at the point of the electrode so as to clog the passage through it, and this is prevented by placing an asbestus thread in the passage. The use of a thread is not essential. All that is required to prevent the clogging of the aperture at the point of the electrode is that a few fibers ot' a refractory material other than carbon should be there present. No deposition or n'lushrooming of the carbon then takes place.

\Vhat I claim is- 1. In an arc lamp, the combination, consisting of carbon electrodes (one or both hollow) connected with an electric source, and usual devices for the production of the electric are between the electrodes, a tightly-fitting fibrous plug inserted a short way up the hollow electrode, a thread of asbestus or refractory fibrous material loosely placed in a space within the electrode between the fibrous plug or packing at one end and the are at the other, and means for supplying liquid hysupply in'gcoal-gas or other illuminating-gas drocarbon to the plug or packing at the end to the electrode up through the hollow or pasfarthest away from the arc. sage therein.

2. In an arc lamp, the combination, eon- 1 LLEWELLYN SAUNDERSON. 5 sisting of carbon electrodes (one or both hol- YVitnesses: 7

low) connected with an electric source, and J NO. H. VVHITEHEAD, usual devices for the product-ion of the elec- 24 Southqmpton Buildings, London, W C. tric are between the electrodes, a thread of T. F. BARNES,

asbestus orrefract'ory fibrous materialloosely Notarys Clerk, 28 Southcmzpton Buildings, [0 placed in the hollow electrode, and means for London, W. C. 

